1. DefinitionsclusterSet of active opixels that illuminates the pupil range through a given lenslet.The number of clusters coincides with that of lenslets.cylinderIn the most general sense, any shape that can be generated by tracing astraight line called a “generant” or “generatrix” along a path, while keepingthe generant parallel to a fixed direction. In some aspects of the presentdevices, the path is a circle, and the generant is perpendicular to the plane ofthe circle. That is the narrowest and commonest sort of “cylinder.” A centralaxis parallel to the generant is then immediately evident. In other aspects ofthe present disclosure, the cylindrical display used can be a cylinder in amore general sense, and references to the “axis” then denote any convenientreference line parallel to the generant. In practical embodiments, thecylindrical surface is usually flat and/or concave towards the eye along itsentire length, with a fairly smooth curve in the curved parts.displayComponent, usually electronic, that modulates the light spatially to produce areal image. The display can be self-emitting, such as an OLED display, orexternally illuminated by a front or a backlight system, such as an LCD or anLCOS. The display may be a digital display that forms a real image from anarray of distinct pixels.eye pupilImage of the interior iris edge through the eye cornea seen from the exteriorof the eye. In visual optics, it is referenced to as the input pupil of the opticalsystem of the eye. Its boundary is typically a circle from 3 to 7 mm diameterdepending on the illumination level.eye sphereSphere centered at the approximate center of the eye rotations and withradius the average distance of the eye pupil to that center (typically 13 mm).field of viewField of View; defined as the horizontal and vertical full angles subtended bythe virtual screen from the eye pupil center when the two eyes rest lookingfrontwards.fixation pointPoint of the scene that is imaged by the eye at center of the fovea, which isthe highest resolution area of the retina.freeformSurface that does not have rotational or linear symmetry. It may have one orsurfacemore planes of symmetry.gaze vectorUnit vector of the direction linking the center of the eye pupil and thefixation point.gazed regionRegion of the virtual screen containing the fixation points for all positions ofof virtualthe eye pupil within the union of the pupil ranges. It contains all the ipixelsscreenthat can be gazed.guardCorridor between adjacent clusters of the digital display that contains noactive opixels. The guard avoids optical cross-talk while guaranteeing certaintolerance for the optics positioning.humanMinimum angle subtended by two point sources which are distinguishable byangularan average perfect-vision human eye. The angular resolution is a function ofresolutionthe peripheral angle and of the illumination level.inactive areaRegion of the digital display in which the opixels are inactive.ipixelVirtual image of the opixels belonging to the same web. Preferably, thisvirtual image is formed at a certain distance from the eye (from 2 m toinfinity). It can also be considered as the pixel of the virtual screen seen bythe eye.lensletEach one of the individual optical devices of the optics array, which collectslight from the digital display and projects it to the eye sphere. The lenslet isdesigned to form a continuous image of opixels into ipixels. Each lenslet maybe formed by one or more optical surfaces. There is one lenslet per clusterand, in time multiplexing, one shutter (or equivalent) per lenslet.opixelPhysical pixel of the digital display. There are active opixels, which are lit tocontribute to the displayed image, and inactive opixels, which are never lit.An inactive opixel can be physically nonexistent, for instance, because thedisplay lacks at that opixel position at least one necessary hardware element(OLED material, electrical connection) to make it functional, or it can beunaddressed by software. The use of inactive opixels reduces the powerconsumption and the amount of information to be managed.opticalUndesired situation in which one opixel is imaged into more than one ipixel.cross-talkouter regionRegion of the virtual screen formed by the ipixels which do not belong to theof virtualgazed region of virtual screen, i.e., it is formed by ipixels that can be seenscreenonly at peripheral angles greater than zero.peripheralAngle formed by a certain direction and the gaze vector.anglepupil range1. Region of the eye sphere illuminated by a single cluster through itscorresponding lenslet. When the eye pupil intersects the pupil range of agiven lenslet, then the image corresponding to its corresponding cluster isprojected on the retina. For a practical immersive design, a pupil rangecomprising a circle of 15 degrees full angle on the eye sphere is sufficient. 2.The union of all pupil ranges corresponding to all lenslets of the array. It is aspherical shell to a good approximation. If all accessible eye pupil positionsfor an average human are considered, the boundary of the union of eye pupilranges is approximately an ellipse with angular horizontal semi-axis of 60degrees and vertical semi-axis of 45 degrees relative to the front direction.surface S1Refractive surface of the lenslet array that is closer to the digital display.surface S2Refractive surface of the lenslet array that is closer to the eye.virtual screenSurface containing the ipixels, preferably being a region of the surface of asphere concentric with the eye and with radius in the range from 2 m toinfinity.webSet of active opixels displaying information of the same ipixel.